"First, what is the big deal with an engine that's able to rev up to 8500 or 9000 rpms? Isn't it your powerband that matters? I don't mean to sound stupid but this confuses me a bit. Every car has peak horsepower and if for example your peak is at like 4200 rpm's - how does being able to rev to 7 or 8 do anything but hurt the engine?"
While revving to 7 or 8k rpm won't hurt an engine that's designed to run that way, you certainly don't want to stay in that area if your powerband is from 2 to 4k rpm...
"how does a 5 inch tip do anything?"
It doesn't. (other than to make an annoying sound) Just like on any other vehicle, a whole cat-back setup may help, and an upgrade from the headers back will certainly help.... but the tip does nothing...
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"The Yellowjacket"
1998 Mustang GT
13.97@103
"Hey, you weren't supposed to be that fast!"- Turbo Eclipse Driver